For the next 3 days, minor G1-class geomagnetic storms are likely, according to NOAA forecasters. The action could begin later today, July 21st, when a slow-moving CME is expected to hit Earth’s magnetic field; it was hurled into space by a solar eruption on July 15th. Forecasters believe a high-speed stream of solar wind is following close behind the CME. Its arrival on July 22nd could amplify any storm the CME creates, prolonging the unrest through July 23rd.

Mike Terry to WOR iog (2022-07-21)